Matrices are essentially tables with numbers. As such, they are as frequent as the tables you create in applications like Microsoft Excel. Many business data are naturally organized as tables. For instance, columns may label various types of merchandise a firm has, while rows list various business metrics of the merchandise (metrics like cost, profit, labor per unit, etc.). However, unlike tables, which just store data, there are meaningful algebraic operations that we can apply to matrices. For instance, matrix multiplication naturally models such fundamental operations as totaling across certain parameters.